PIV studies on reverse flow in a channel without obstruction at the entry

Abstract

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.

It is known that reverse flow (i.e. flow in the direction opposite to the free stream) occurs when an obstruction is placed near the entry region of a channel (referred to as the test channel), kept inside another wider channel. The present investigation is focused on realizing reverse flow in the test channel without an obstruction placed at the entry. Experiments in water channel have been carried out along with visualization of the flow using PIV. The initial stages of the investigation revealed that the test channel with the two walls, forming the channel having a stagger with respect to each other and at an angle of attack would result in reverse flow even without an obstruction. Studies have been carried out for different widths (gap between the two walls forming the channel), and at an angle of attack of 30⁰.